germ layer

American  

noun

1. one of the three primary embryonic cell layers.

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germ layer British  

noun

1. embryol any of the three layers of cells formed during gastrulation See ectoderm mesoderm endoderm

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germ layer Scientific  

1. Any of three cellular layers, the ectoderm, endoderm, or mesoderm, into which most animal embryos differentiate in the gastrula stage and from which the organs and tissues of the body develop through further differentiation.

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Etymology

Origin of germ layer

First recorded in 1875–80

Example Sentences

That’s also true for this week’s recipe: a no-bake cheesecake with a ginger-pear filling, finished with a generous layer of granola.

From Salon • Oct. 23, 2025

To assemble the sandwiches, spread a generous layer of the chutney on the bottom bun.

From Washington Post • Mar. 30, 2022

And then my secret ingredient: A generous layer of shredded halva on top.

From Washington Times • Jul. 13, 2020

A thick layer of buttery shortbread is the base, baked in a square cake pan, with a generous layer of crisp pecans on top.

From New York Times • Nov. 4, 2016

Not only did he seem to be able to grow facial hair overnight, but a generous layer of black hair covered his arms and legs.

From "The City Beautiful" by Aden Polydoros